Integrated optics units and methods of manufacturing integrated optics units for use with microelectronic imagers

ABSTRACT

Microelectronic imagers, optical devices for microelectronic imagers, methods for manufacturing integrated optical devices for use with microelectronic imagers, and methods for packaging microelectronic imagers. The optical devices are manufactured in optical device assemblies that provide efficient and highly accurate fabrication of the optics that are used in microelectronic imagers. The optical device assemblies are particularly useful for packaging a plurality of microelectronic imagers at the wafer level. Wafer-level packaging is expected to significantly enhance the efficiency of manufacturing microelectronic imagers because a plurality of imagers can be packaged simultaneously using highly accurate and efficient processes developed for packaging processors, memory devices and other semiconductor devices.

TECHNICAL FIELD

The following disclosure relates generally to microelectronic devicesand methods for packaging microelectronic devices. Several aspects ofthe present invention are directed toward packaging microelectronicimagers that are responsive to radiation in the visible light spectrumor radiation in other spectrums.

BACKGROUND

Microelectronic imagers are used in digital cameras, wireless deviceswith picture capabilities, and many other applications. Cell phones andPersonal Digital Assistants (PDAs), for example, are incorporatingmicroelectronic imagers for capturing and sending pictures. The growthrate of microelectronic imagers has been steadily increasing as theybecome smaller and produce better images with higher pixel counts.

Microelectronic imagers include image sensors that use Charged CoupledDevice (CCD) systems, Complementary Metal-Oxide Semiconductor (CMOS)systems, or other systems. CCD image sensors have been widely used indigital cameras and other applications. CMOS image sensors are alsoquickly becoming very popular because they are expected to have lowproduction costs, high yields and small sizes. CMOS image sensors canprovide these advantages because they are manufactured using technologyand equipment developed for fabricating semiconductor devices. CMOSimage sensors, as well as CCD image sensors, are accordingly “packaged”to protect the delicate components and to provide external electricalcontacts.

FIG. 1 is a schematic view of a conventional microelectronic imager 1with a conventional package. The imager 1 includes a die 10, aninterposer substrate 20 attached to the die 10, and a housing 30attached to the interposer substrate 20. The housing 30 surrounds theperiphery of the die 10 and has an opening 32. The imager 1 alsoincludes a transparent cover 40 over the die 10.

The die 10 includes an image sensor 12 and a plurality of bond-pads 14electrically coupled to the image sensor 12. The interposer substrate 20is typically a dielectric fixture having a plurality of bond-pads 22, aplurality of ball-pads 24, and traces 26 electrically coupling bond-pads22 to corresponding ball-pads 24. The ball-pads 24 are arranged in anarray for surface mounting the imager 1 to a board or module of anotherdevice. The bond-pads 14 on the die 10 are electrically coupled to thebond-pads 22 on the interposer substrate 20 by wire-bonds 28 to provideelectrical pathways between the bond-pads 14 and the ball-pads 24.

The imager 1 shown in FIG. 1 also has an optics unit including a support50 attached to the housing 30 and a barrel 60 adjustably attached to thesupport 50. The support 50 can include internal threads 52, and thebarrel 60 can include external threads 62 engaged with the threads 52.The optics unit also includes a lens 70 carried by the barrel 60.

One problem with packaging conventional microelectronic imagers is thatit is difficult to accurately align the lens with the image sensor.Referring to FIG. 1, the centerline of the lens 70 should be alignedwith the centerline of the image sensor 12 within very tight tolerances.For example, as microelectronic imagers have higher pixel counts andsmaller sizes, the centerline of the lens 70 is often required to bewithin a few microns of the centerline of the image sensor 12. This isdifficult to achieve with conventional imagers because the support 50may not be positioned accurately on the housing 30, and the barrel 60 ismanually threaded onto the support 50. Therefore, there is a need toalign lenses with image sensors with greater precision in moresophisticated generations of microelectronic imagers.

Another problem of packaging conventional microelectronic imagers isthat positioning the lens at a desired focus distance from the imagesensor is time-consuming and may be inaccurate. The lens 70 shown inFIG. 1 is spaced apart from the image sensor 12 at a desired distance byrotating the barrel 60 (arrow R) to adjust the elevation (arrow E) ofthe lens 70 relative to the image sensor 12. In practice, an operatorrotates the barrel 60 by hand while watching an output of the imager 1on a display until the picture is focused based on the operator'ssubjective evaluation. The operator then adheres the barrel 60 to thesupport 50 to secure the lens 70 in a position where it is spaced apartfrom the image sensor 12 by a suitable focus distance. This process isproblematic because it is exceptionally time-consuming and subject tooperator errors.

Yet another concern of conventional microelectronic imagers is that theyhave relatively large footprints and occupy a significant amount ofvertical space (i.e., high profiles). The footprint of the imager inFIG. 1 is the surface area of the bottom of the interposer substrate 20.This is typically much larger than the surface area of the die 10 andcan be a limiting factor in the design and marketability of picture cellphones or PDAs because these devices are continually shrinking to bemore portable. Therefore, there is a need to provide microelectronicimagers with smaller footprints and lower profiles.

Yet another concern of conventional microelectronic imagers is themanufacturing costs for packaging the dies. The imager 1 shown in FIG. 1is relatively expensive because manually adjusting the lens 70 relativeto the image sensor 12 is very inefficient and subject to error.Moreover, the support 50 and barrel 60 are assembled separately for eachdie 10 individually after the dies have been singulated from a wafer andattached to the interposer substrate 20. Therefore, there is asignificant need to enhance the efficiency, reliability and precision ofpackaging microelectronic imagers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a packaged microelectronic imager inaccordance with the prior art.

FIG. 2A is a side cross-sectional view of an imager workpiece having aplurality of imaging units and an optical device assembly having aplurality of optical devices in accordance with an embodiment of theinvention at one stage of packaging microelectronic imagers at the waferlevel.

FIG. 2B is a side cross-sectional view of a plurality of assembledmicroelectronic imagers including the imager workpiece and the opticaldevice assembly of FIG. 2A in accordance with an embodiment of theinvention.

FIGS. 3A and 3B are schematic cross-sectional views illustrating onemethod for manufacturing an optical device assembly in accordance withan embodiment of the invention.

FIG. 4 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

FIG. 5 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

FIG. 6 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

FIGS. 7A and 7B are schematic cross-sectional views illustrating amethod for manufacturing an optical device assembly in accordance withanother embodiment of the invention.

FIGS. 8A and 8B are schematic cross-sectional views illustrating amethod for manufacturing an optical device assembly in accordance withanother embodiment of the invention.

FIGS. 9A and 9B are schematic cross-sectional views illustrating amethod for manufacturing an optical device assembly in accordance withanother embodiment of the invention.

FIG. 10 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

FIG. 11 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

FIG. 12 is a schematic cross-sectional view illustrating an opticaldevice assembly in accordance with another embodiment of the invention.

DETAILED DESCRIPTION

A. Overview

The following disclosure describes several embodiments ofmicroelectronic imagers, optical devices for microelectronic imagers,methods for manufacturing integrated optical devices for use withmicroelectronic imagers, and methods for packaging microelectronicimagers. The optical devices are manufactured together on an opticaldevice assembly that provides efficient and highly accurate fabricationof the optics that are used in microelectronic imagers. Such opticaldevice assemblies are particularly useful for wafer-level packaging of aplurality of microelectronic imagers. Wafer-level packaging is expectedto significantly enhance the efficiency of manufacturing microelectronicimagers because a plurality of imagers can be packaged simultaneouslyusing highly accurate and efficient processes developed for packagingprocessors, memory devices and other semiconductor devices. Moreover,wafer-level packaging is also expected to enhance the quality andperformance of microelectronic imagers because the semiconductorfabrication processes can reliably align an optical device with an imagesensor and space the optical device apart from the image sensor by adesired distance with a high degree of precision. Several embodiments ofmicroelectronic imagers and methods for packaging microelectronicimagers in accordance with the invention are thus expected tosignificantly reduce the costs for assembling microelectronic imagers,increase the performance of microelectronic imagers, and produce smallerimagers compared to conventional devices.

An aspect of the invention is directed toward methods for fabricating aplurality of optical devices for use in microelectronic imagers. Oneembodiment of such a method comprises providing a substrate having aplurality of discrete device sites and producing a plurality of opticselements located at the device sites. The substrate is transmissive to adesired radiation, such as light in the visible spectrum, ultravioletlight, infrared radiation and/or other spectrums. The substrate can beglass, quartz, plastics or other materials suitable for a particularapplication. The optics elements are configured to manipulate theradiation passing through the optical devices. The optics elements, forexample, can include lenses that direct the radiation (e.g., membershaving curved surfaces and/or pin-holes), filters and/or other optics.The optics elements and the substrate together define an optical deviceassembly having a plurality of discrete optical devices.

Another embodiment of a method for fabricating a plurality of opticaldevices in accordance with the invention comprises providing a substratethat is transmissive to a desired radiation. The substrate has a firstdevice site for a first optical device and a second device site for asecond optical device. The first and second optical device sites areseparated by a cutting line for subsequently separating the firstoptical device from the second optical device. This embodiment alsoincludes producing first and second lenses. The first lens is located atthe first device site to define the first optical device, and the secondlens is located at the second device site to define the second opticaldevice.

Still another embodiment of a method for fabricating optical devices inaccordance with the invention includes providing a substratetransmissive to the desired radiation and producing a plurality ofoptics elements simultaneously at different device sites of thesubstrate. The optics elements are produced simultaneously usinginjection molding process, etching procedures or other suitabletechniques. As such, this method involves concurrently forming aplurality of optical devices on the substrate.

Another aspect of the present invention is directed towards opticaldevice assemblies having a plurality of individual optical devices. Oneembodiment of an optical device assembly in accordance with theinvention comprises a substrate transmissive to a desired radiation. Thesubstrate has a plurality of discrete device sites. The optical deviceassembly of this embodiment further includes a plurality of opticselements that are configured to direct radiation passing through theoptics elements for use with microelectronic imagers. The opticselements are located at corresponding device sites of the substrate toform individual optical devices.

Another embodiment of an optical device assembly in accordance with theinvention comprises a plurality of discrete optical devices on a singlesubstrate that is transmissive to a desired radiation. Each opticaldevice includes an optics element configured to direct radiation passingthrough the optical device. The optics elements are separated from eachother on the substrate by cutting lanes for subsequently cutting thesubstrate to separate individual optical devices from each other.

Still another embodiment of an optical device assembly in accordancewith the invention comprises a substrate transmissive to a desiredradiation. The substrate has a first device site and a second devicesite. The optical device assembly further includes a first opticselement at the first device site to form a first optical device and asecond optics element at the second device site to form a second opticaldevice. The first and second optics elements are separated by a cuttingline to subsequently separate the first optical device from the secondoptical device.

Specific details of several embodiments of the invention are describedbelow with reference to CMOS imagers to provide a thorough understandingof these embodiments, but other embodiments can be CCD imagers or othertypes of imagers. Several details describing well-known structures oftenassociated with microelectronic devices are not set forth in thefollowing description to avoid unnecessarily obscuring the descriptionof the disclosed embodiments. Additionally, several other embodiments ofthe invention can have different configurations or components than thosedescribed in this section. As such, a person of ordinary skill in theart will accordingly understand that the invention may have otherembodiments with additional elements or without several of the elementsshown and described below with reference to FIGS. 2A-12.

B. Wafer-Level Packaging Of Microelectronic Imagers

FIG. 2A is a side cross-sectional view showing a portion of awafer-level assembly 200 including an imager workpiece 202 and anoptical device assembly 204 aligned with each other for wafer-levelpackaging of microelectronic imagers. The imager workpiece 202 has afirst substrate 210 and a plurality of imaging units 212 formed on thefirst substrate 210. Individual imaging units 212 can include an imagesensor 214, integrated circuitry (IC) 216 coupled to the image sensor214, and external contacts 220 electrically coupled to the integratedcircuitry 216. The image sensor 214 can be a CMOS device or a CCD forcapturing pictures or other images in the visible spectrum, but theimage sensor 214 can detect radiation in other spectrums (e.g., IR or UVranges). The embodiment of the external contacts 220 shown in FIG. 2Aprovides a small array of ball-pads within the footprint of the die.Each external contact 220, for example, can include a bond-pad 222, aball-pad 224, and a through-wafer interconnect 226 coupling the bond-pad222 to the ball-pad 224. The through-wafer interconnects 226 can beformed according to the processes disclosed in U.S. patent applicationSer. No. 10/713,878, entitled “Microelectronic Devices, Methods forForming Vias in Microelectronic Devices, and Methods for PackagingMicroelectronic Devices,” filed on Nov. 13, 2003 (Perkins Coie DocketNo. 10829.8742US00), which is incorporated by reference herein. Otherembodiments of external contacts can include contacts having traces thatwrap around the side of the substrate 210.

The imaging units 212 can also include first referencing elements 230.The first reference elements 230 can be components of stand-offs forattaching the optical device assembly 204 to the imager workpiece 202.The first referencing elements 230 can be similar to the firstreferencing elements shown and described in U.S. patent application Ser.No. 10/723,363, entitled “Packaged Microelectronic Imagers and Methodsfor Packaging Microelectronic Imagers,” filed on Nov. 26, 2003 (PerkinsCoie Docket No. 10829.8746US00), which is incorporated by referenceherein.

The optical device assembly 204 includes include a second substrate 250and a plurality of optical devices 260 on the second substrate 250.Individual optical devices 260 can include an optics element 270 and asecond referencing element 280. The first and second referencingelements 230 and 280 are configured to be keyed together or otherwiseseat with each other in a manner that aligns individual optics elements270 with corresponding image sensors 214. The first and secondreferencing elements 230 and 280 are also configured to space theindividual optics elements 270 apart from corresponding image sensors214 by a desired distance. The second referencing elements 280 can besimilar to the second referencing elements shown U.S. patent applicationSer. No. 10/723,363 incorporated by reference above. The stand-offsbetween the optical devices 260 and the imaging units 212, however, donot need to have separate referencing elements as shown in FIG. 2A. Thestand-offs can accordingly be single components constructed on just oneof the first or second substrates 210 or 250.

FIG. 2B is a schematic cross-sectional view illustrating a plurality ofmicroelectronic imagers 290 that have been packaged at the wafer level.The imagers 290 can be assembled by seating individual first referencingelements 230 with corresponding second referencing elements 280. In oneembodiment, the first and second referencing elements 230/280 are seatedtogether before cutting the first substrate 210 or the second substrate250 such that all of the microelectronic imagers 290 are assembled atthe wafer level. Both of the first and second substrates 210 and 250 canthen be cut along lines A-A to separate individual imagers 290 from eachother. In a different embodiment, the individual microelectronic imagersare formed by cutting the second substrate 250 along lines B-B (FIG. 2A)to singulate the individual optics units 260, attaching the individualoptics units 260 to corresponding imaging units 212 before cutting thefirst substrate 210, and then cutting the first substrate 210 alonglines A-A to singulate individual imagers. In still another embodiment,the first substrate 210 can be cut along lines A-A (FIG. 2A) tosingulate the imaging units 212, and only the known good imaging units212 are then mounted to corresponding optics units 260 either before orafter singulating the second substrate 250 along lines B-B (FIG. 2B).

In an alternative embodiment, the wafer-level assembly 200 can furtherinclude a second optical device assembly 204′ (shown in phantom) on topof the optical device assembly 204. The second optical device assembly204′ can be similar to the first optical device assembly, or it can havedifferent lenses, height, etc. Additionally, still other embodiments ofwafer-level assemblies can have more than two optical device assembliesstacked on each other such that three or more levels of focusing lenses,dispersion lenses, pin-hole lenses, filters, anti-reflective members orother types of optics can be above the image sensors.

The wafer-level packaging of the microelectronic imagers 290 shown inFIG. 2B is enabled, at least in part, by forming an optical deviceassembly with a plurality of individual optical devices arranged in apattern corresponding to the arrangement of imaging units 212 on theimaging workpiece 202. Several embodiments of optical device assembliesand methods for manufacturing such optical device assemblies aredescribed below.

C. Optical Device Assemblies For Microelectronic Imagers

FIGS. 3A-12 illustrate several different optical device assemblies andmethods for fabricating a plurality of optical devices on a substrate inaccordance with embodiments of the invention. The optical deviceassemblies shown in FIGS. 3A-12 can all be used to packagemicroelectronic imagers at the wafer level as described above withreference to FIGS. 2A-B. Therefore, additional embodiments of theinvention are directed to packaging microelectronic imagers at the waferlevel using any of the optical device assemblies illustrated in FIGS.3A-12 and/or other optical devices having any combination of thefeatures shown in these Figures.

FIGS. 3A and 3B are schematic cross-sectional views illustrating amethod for manufacturing an optical device assembly 300 (FIG. 3B) inaccordance with an embodiment of the invention. The optical deviceassembly 300 includes a substrate 310 having a first side 312 and asecond side 314. The substrate 310 further includes a plurality ofdiscrete device sites 320 at which individual optical devices 330 (FIG.3B) are constructed on and/or in the substrate 310. The boundaries ofthe device sites 320 can be defined by cutting lanes C-C along which thesubstrate 310 can be cut to singulate individual optical devices fromeach other.

The substrate 310 is transmissive to a desired radiation. When theimagers are for use in cameras, for example, the substrate istransmissive to light in the visible spectrum. The substrate 310,however, can be transmissive to ultraviolet light, infrared radiationand/or any other suitable spectrum according to the particularapplication of the imager. The substrate 310 can be composed of glass,quartz, plastics and/or other materials. The substrate 310 can also beconfigured to be handled by semiconductor fabrication equipment. Assuch, the substrate 310 can be a thin wafer having a thickness ofapproximately 150-1,500 μm and a diameter of approximately 200-300 mm,or it can have other dimensions suitable for being handled by automaticfabrication equipment.

Referring to FIG. 3B, the method continues by producing a plurality ofoptics elements 350 on the substrate 310. The optical device assembly300 typically has an optics element 350 at each of the device sites 320.The optics elements 350 can be on the first side 312 and/or the secondside 314 of the substrate 310. For example, the optics elements 350 caninclude a first optic member (shown in solid lining) on the first side312 of the substrate 310 at the device sites 320. In other embodiments,the optics elements 350 can include a second optic member (shown inbroken lining) on the second side 314 of the substrate 310 in additionto or in lieu of the first optic member.

The optics elements 350 are configured to manipulate the radiation foruse by the image sensors 214 (FIG. 2B). For example, the optics elements350 can be lenses that direct the radiation 350 for focusing, dispersingand/or removing higher order defractions from the radiation. Such opticselements 350 can be lenses having a curvature and/or a pin-holeaperture. As explained in more detail below, the optics elements 350 canbe produced by molding a compound onto the substrate 310 or separatelyfrom the substrate 310, etching the substrate 310 or a layer of materialon the substrate 310, and/or attaching individual optics elements to thesubstrate 310.

FIG. 4 is a schematic cross-sectional view illustrating an opticaldevice assembly 400 in accordance with another embodiment of theinvention. The optical device assembly 400 is similar to the opticaldevice 300, and thus like reference numbers refer to like components inthese figures. The optical device assembly 400 is different than theoptical device assembly 300 in that the optical device assembly 400includes a filter 410 on the substrate 310. The filter 410 can be a thinfilm or film stack having a plurality of films deposited onto the firstor second sides 312/314 of the substrate 310. The filter 410, forexample, can be an IR filter to prevent infrared radiation from passingthrough the optics elements 350. The filter 410 can have several otherembodiments for filtering other spectrums in addition to or in lieu ofinfrared radiation. In other embodiments, the filter 410 can be formedon the optics elements 350 instead of the substrate 310. The filter 410can accordingly be a layer of material that is “over” the substrate 310in the sense that it can be directly on the substrate 310 or on acomponent attached to the substrate 310.

FIG. 5 is a schematic cross-sectional view illustrating an opticaldevice assembly 500 in accordance with another embodiment of theinvention. Like reference numbers refer to like components in FIGS. 3Band 5. The optical device assembly 500 has a plurality of opticselements 550, and each optics element 550 is located at a device site320. The optics elements 550 shown in FIG. 5 are formed with a commonbase 551, and each optics element 550 has a lens 552 including a curvedsurface 560 for directing the radiation as it passes through the opticselements 550. The curved surfaces 560, which are shown schematically inFIG. 5, can have any combination of convex and/or concave curvatureswith respect to the substrate 310 to provide the desired optics.

The optics elements 550 shown in FIG. 5 are formed by molding a compoundto form the base 551 and individual lenses 552. For example, the opticselements 550 can be formed in an injection molding process in which thebase 551 is molded onto the substrate 310 and the lenses 552 are moldedintegrally with the base 551. Alternatively, the optics elements 550 canbe molded separately from the substrate 310 as a single unit, and thenthe base 551 is attached to the substrate 310 with an adhesive. Theoptics elements 550 are accordingly made from a suitable compound suchas glass, quartz, plastics and/or other materials that can be moldedinto the desired shape and provide the desired transmission propertiesfor the radiation.

Several embodiments of the optical device assemblies shown in FIGS. 2A-5can be used to enable wafer-level packaging processes for imagers in amanner that is expected to significantly improve the quality of theimagers. Compared to conventional processes for assemblingmicroelectronic imagers by hand, the optical device assemblies describedabove enhance (a) the ability to produce very small optics elementswithin demanding tolerances, (b) the accuracy with which the opticselements are aligned with corresponding image sensors, and/or (c) theaccuracy with which the optics elements are spaced apart from the imagesensors by a desired distance. One aspect of the optical devices is thatthey are fabricated on a wafer and then assembled with imaging unitsusing semiconductor processing technologies. This provides very precisetolerances for the optics elements, and it also enables highly accuratepositioning/placement of the optical devices relative to the imagesensors. Thus, the embodiments of the optical device assemblies in FIGS.2A-5 can enable smaller and/or higher performance packages because theycan be formed and assembled with a high degree of precision.

Several embodiments of these optical device assemblies are furtherexpected to be a factor in wafer-level packaging processes that improvethe efficiency of packaging imagers compared to the manual process ofpackaging the conventional imager shown in FIG. 1. First, a plurality ofimaging units and optics elements can be fabricated simultaneously atthe wafer level using semiconductor fabrication techniques. Second, aplurality of the optical devices can be attached to a correspondingplurality of the imaging units at the wafer level using automatedequipment. This accordingly eliminates manually positioning individuallenses with respect to imaging sensor, which should significantlyenhance the throughput and yield of packaging microelectronic imagers.

FIG. 6 is a schematic cross-sectional view illustrating an opticaldevice assembly 600 in accordance with another embodiment of theinvention. The optical device assembly 600 is substantially similar tothe optical device assembly 500 shown in FIG. 5, but the optical deviceassembly 600 includes a filter 610 between the substrate 310 and theoptics elements 550. As explained above, the filter 610 can be on theother side of the substrate 310 or on the exterior surfaces of theoptics elements 550. The filter 610 removes undesirable radiation frompassing through the optical devices.

FIGS. 7A and 7B are schematic cross-sectional views illustrating amethod for manufacturing an optical device assembly 700 (FIG. 7B) inaccordance with another embodiment of the invention. Referring to FIG.7A, this method includes providing a substrate 701 having a first side702, a second side 704, and a plurality of the device sites 320. Thesubstrate 701 shown in FIG. 7A is substantially similar to the substrate310 shown in FIG. 3A, but the substrate 701 is patterned with a hardmask 710 (shown schematically without a pattern of apertures) to formthe optics elements by etching the substrate 701. The mask 710 can be alayer of resist or other material that is patterned as known in the artof semiconductor manufacturing.

FIG. 7B illustrates the optical device assembly 700 after etching aplurality of optics elements 750 into the substrate 701. The opticselements 750 typically include a curved surface 760 that can have anydesired curvature as described above with reference to the curvedsurface 560 (FIG. 5). The optics elements 750 are typically etched usinga plurality of separate mask/etch steps to form the desired curvature(s)for the curved surfaces 760. The particular mask/etch steps can bedeveloped according to the parameters of the particular design of theoptical devices using mask/etch technology developed in semiconductormanufacturing.

FIGS. 8A and 8B are schematic cross-sectional views of a method formanufacturing an optical device assembly 800 (FIG. 8B) in accordancewith another embodiment of the invention. The optical device assembly800 is fabricated using an etching process that is similar to theprocess described above with reference to FIGS. 7A-B. Referring to FIG.8A, the optical device assembly 800 is constructed by providing asubstrate 810 having a first side 812 and a second side 814. This methodcontinues by depositing a layer of lens material 816 onto the substrate810 and patterning the layer of lens material 816 with a mask 818 (shownschematically without apertures). Referring to FIG. 8B, the layer oflens material 816 is etched using one or more mask/etch steps to form aplurality of optics elements 850 on the substrate 810. The opticselements 850 are located at corresponding device sites 320, and theoptics elements 850 have a desired surface 860 for manipulating theradiation as it passes through the optics elements 850. The opticselements 850 can be different from the optics elements 750 shown in FIG.7B in that the optics elements 850 can be composed of a differentmaterial than a substrate 810. For example, the substrate 810 can be aquartz plate and the optics elements 850 can be plastic or anothermaterial having the desired configuration and transmissiveness tomanipulate the radiation accordingly.

FIGS. 9A and 9B are schematic cross-sectional views illustrating anothermethod for manufacturing a device assembly 900 (FIG. 9B) in accordancewith an embodiment of the invention. The optical device assembly 900includes the substrate 310 described above and a plurality of separateoptics elements 950. The optics elements 950 are produced by moldingand/or etching lenses separately from the substrate 310 and thenattaching the lenses to the substrate. In one embodiment, the opticselements 950 are etched from a substrate made from the same material ora different material than that of the substrate 310. Alternatively, theoptics elements 950 are molded either as a single unit that issubsequently cut or as individual pieces. Referring to FIG. 9B, theoptics elements 950 are attached to the substrate 310 at the devicesites 320 to form a plurality of optical devices 960 on the opticaldevice assembly 900.

The various features illustrated in the optical device assemblies shownin FIGS. 3A-9B can be combined to form other optical device assemblies.FIGS. 10 and 11, for example, are schematic cross-sectional viewsillustrating optical device assemblies 1000 and 1100 in accordance withadditional embodiments of the invention. The optical device assembly1000 shown in FIG. 10 can have a first section 1002 and a second section1004. The first section 1002 can include a plurality of first opticmembers 1010 having first curved surfaces 1012, and the second section1004 can have a plurality of second optic members 1020 having secondcurved surfaces 1022. The first and second curved surfaces 1012 and 1022can be different from one another according to the particularapplications of the microelectronic imager. The first and second opticmembers 1010 and 1020 together define discrete optics elements 1050 atthe device sites 320.

The first section 1002 can be formed by molding a material to shape thefirst optic members 1010 on a base 1014. The base 1014 can becharacterized as a substrate in the sense that it interconnects thefirst optic members 1010 to form an integrated unit for wafer levelprocessing. Alternatively, the first section 1002 can be formed byetching the first optic members 1010 from a substrate. The secondsection 1004 can be formed by etching or molding the second opticmembers 1020 in a manner similar to the first section 1002. The firstand second sections 1002 and 1004 are then assembled to form the opticaldevice assembly 1000.

The optical device assembly 1100 shown in FIG. 11 illustrates anothercombination of components. The optical device assembly 1100 includes thesubstrate 310, a first section 1102 having a plurality of first opticmembers 1110 on one side of the substrate 310, and a second section 1104having a plurality of second optic members 1120 on the other side of thesubstrate 310. The first section 1102 can be similar to the moldedoptics elements 550 shown in FIGS. 5 and 6, or the etched opticselements 750 shown in FIG. 7B. The optic members 1120 of the secondsection 1104 can be similar to the optics elements 850 shown in FIG. 8Bor the optics elements 950 shown in FIG. 9B.

FIG. 12 is a schematic cross-sectional view illustrating another opticaldevice assembly 1200 in accordance with another embodiment of theinvention. The optical device assembly 1200 includes the substrate 310with the device sites 320 and a plurality of optics elements 1250 at thedevice sites 320. The optics elements 1250 can include a first section1202 and a second section 1204. The first section 1202 provides aplurality of pin-hole apertures 1260 defined by openings in a layer1262. The second section 1204 can include a plurality of second opticmembers 1270. The first optic members 1260 and the second optic members1270 together define the optics elements 1250. The second optic members1270 can be formed according to any of the embodiments for constructingthe optics elements shown in FIGS. 3A-11.

From the foregoing, it will be appreciated that specific embodiments ofthe invention have been described herein for purposes of illustration,but that various modifications may be made without deviating from thespirit and scope of the invention. For example, the pin-hole lensesshown in FIG. 12 can be combined with any of the optical deviceassemblies shown in FIGS. 3A-11. Additionally, the term substrate caninclude wafer-like substrates and/or molded base sections of the opticaldevice assemblies. Accordingly, the invention is not limited except asby the appended claims.

1. A method of fabricating a plurality of optical devices for use inmicroelectronic imagers, comprising: providing a substrate having aplurality of device sites, the substrate being transmissive to a desiredradiation; and producing a plurality of discrete optics elementsconfigured to manipulate the radiation, wherein individual opticselements are located at corresponding individual device sites of thesubstrate to form a plurality of discrete optical devices.
 2. The methodof claim 1 wherein: providing the substrate comprises providing a waferthat is transmissive to light in the visible spectrum and configured tobe processed in semiconductor fabrication tools; producing a pluralityof optics elements comprises molding lenses onto the wafer and formingpin-hole apertures across the wafer at the device sites, the lenseshaving a curved surface to direct the radiation; and the method furthercomprises forming a filter over the wafer.
 3. The method of claim 1wherein: providing the substrate comprises providing a wafer that istransmissive to light in the visible spectrum and configured to beprocessed in semiconductor fabrication tools; producing a plurality ofoptics elements comprises etching lenses into the wafer and formingpin-hole apertures across the wafer at the device sites, the lenseshaving a curved surface to direct the radiation; and the method furthercomprises forming a filter over the wafer.
 4. The method of claim 1wherein: providing the substrate comprises providing a wafer that (a) istransmissive to light in the visible spectrum, (b) includes a layer oflens material, and (c) is configured to be processed in semiconductorfabrication tools; producing a plurality of optics elements comprisesetching lenses into the layer of lens material and forming pin-holeapertures across the wafer at the device sites, the lenses having acurved surface to direct the radiation; and the method further comprisesforming a filter over the wafer.
 5. The method of claim 1 wherein:providing the substrate comprises providing a wafer that is transmissiveto light in the visible spectrum and configured to be processed insemiconductor fabrication tools; producing a plurality of opticselements comprises forming a plurality of lenses separately from thewafer, attaching individual lenses to the wafer at corresponding devicesites, and forming pin-hole apertures across the wafer at the devicesites, the lenses having a curved surface to direct the radiation; andthe method further comprises forming a filter over the wafer.
 6. Themethod of claim 1 wherein providing the substrate comprises providing awafer that is transmissive to light in the visible spectrum andconfigured to be processed in semiconductor fabrication tools.
 7. Themethod of claim 6 wherein producing a plurality of optics elementscomprises molding lenses onto the wafer at the device sites.
 8. Themethod of claim 6 wherein producing a plurality of optics elementscomprises etching lenses into the wafer at the device sites.
 9. Themethod of claim 6 wherein producing a plurality of optics elementscomprises etching lenses into a layer of lens material on the wafer atthe device sites.
 10. The method of claim 6 wherein producing aplurality of optics elements comprises forming a plurality of lensesseparately from the wafer and attaching the lenses to the wafer at thedevice sites.
 11. The method of claim 1 wherein providing the substratecomprises providing a quartz wafer.
 12. The method of claim 11 whereinproducing a plurality of optics elements comprises molding lenses ontothe wafer to form a lens at each device site.
 13. The method of claim 11wherein producing a plurality of optics elements comprises etchinglenses into the quartz wafer such that a lens is located at each devicesite.
 14. The method of claim 11 wherein producing a plurality of opticselements comprises forming a plurality of lenses separately from thewafer and attaching a lens to the wafer at each device site.
 15. Themethod of claim 1 wherein producing a plurality of optics elementscomprises forming a plurality of first lens members and a plurality ofsecond lens members, and wherein each device site has a lens comprisinga first lens member and a second lens member.
 16. The method of claim 1,further comprising forming pin-hole apertures across the substrate atthe device sites.
 17. The method of claim 16 wherein forming pin-holeapertures comprises depositing a non-transmissive layer onto thesubstrate and removing portions of the non-transmissive layer to formopenings at the device sites.
 18. The method of claim 1, furthercomprising forming a filter on the substrate.
 19. The method of claim 18wherein forming a filter on the substrate comprises depositing a firstfilm on the substrate that filters the radiation.
 20. The method ofclaim 1, further comprising cutting the substrate to separate individualoptical devices from one another.
 21. A method of fabricating aplurality of optical devices for use in microelectronic imagers,comprising: providing a substrate transmissive to a desired radiation,the substrate having a first device site for a first optical device anda second device site for a second optical device, and the first devicesite being separated from the second device site by a cutting lane forsubsequently separating the first optical device from the second opticaldevice; and producing a first lens and a second lens, the first lensbeing located at the first device site of the substrate to define thefirst optical device and the second lens being located at the seconddevice site of the substrate to define the second optical device. 22.The method of claim 21 wherein providing the substrate comprisesproviding a wafer that is transmissive to light in the visible spectrumand configured to be processed in semiconductor fabrication tools. 23.The method of claim 22 wherein producing the first and second lensescomprises molding the first and second curved surfaces located onto thewafer at the first and second device sites, respectively.
 24. The methodof claim 22 wherein producing the first and second lenses comprisesetching first and second curved surfaces into the wafer at the first andsecond device sites, respectively.
 25. The method of claim 22 whereinproducing the first and second lenses comprises etching first and secondcurved surfaces into a layer of lens material on the wafer at the devicesites, respectively.
 26. The method of claim 22 wherein producing thefirst and second lenses comprises forming a first lens with a firstcurved surface and a second lens with a second curved surface separatelyfrom the wafer and attaching the first and second lenses to the wafer atthe first and second device sites, respectively.
 27. The method of claim21 wherein: providing the substrate comprises providing a wafer that istransmissive to light in the visible spectrum and configured to beprocessed in semiconductor fabrication tools; producing the first andsecond lenses comprises molding the first and second curved surfacesonto the wafer at the first and second device sites, respectively, andforming pin-hole apertures across the wafer at the device sites; and themethod further comprises forming a filter over the wafer.
 28. The methodof claim 21 wherein: providing the substrate comprises providing a waferthat is transmissive to light in the visible spectrum and configured tobe processed in semiconductor fabrication tools; producing the first andsecond lenses comprises etching first and second curved surfaces intothe wafer at the first and second device sites, respectively, andforming pin-hole apertures across the wafer at the device sites; and themethod further comprises forming a filter over the wafer.
 29. The methodof claim 21 wherein: providing the substrate comprises providing a waferthat (a) is transmissive to light in the visible spectrum, (b) includesa layer of lens material, and (c) is configured to be processed insemiconductor fabrication tools; producing the first and second lensescomprises etching first and second curved surfaces into a layer of lensmaterial on the wafer at the device sites, respectively, and formingpin-hole apertures across the wafer at the device sites; and the methodfurther comprises forming a filter over the wafer.
 30. The method ofclaim 21 wherein: providing the substrate comprises providing a waferthat is transmissive to light in the visible spectrum and configured tobe processed in semiconductor fabrication tools; producing the first andsecond lenses comprises forming a first lens with a first curved surfaceand a second lens with a second curved surface separately from the waferand attaching the first and second lenses to the wafer at the first andsecond device sites, respectively, and forming pin-hole apertures acrossthe wafer at the device sites, the lenses having a curved surface todirect the radiation; and the method further comprises forming a filterover the wafer.
 31. A method of fabricating optical devices for use inmicroelectronic imagers, comprising: providing a substrate transmissiveto the desired radiation, the substrate having a plurality of discretedevice sites for forming individual optical devices; producing aplurality of optics elements simultaneously at the device sites toconcurrently form a plurality of individual optical devices on thesubstrate.
 32. The method of claim 31 wherein providing the substratecomprises providing a wafer that is transmissive to light in the visiblespectrum and configured to be processed in semiconductor fabricationtools.
 33. The method of claim 32 wherein producing a plurality ofoptics elements comprises molding lenses onto the wafer at the devicesites.
 34. The method of claim 32 wherein producing a plurality ofoptics elements comprises etching lenses into the wafer at the devicesites.
 35. The method of claim 32 wherein producing a plurality ofoptics elements comprises etching lenses into a layer of lens materialon the wafer at the device sites.
 36. The method of claim 32 whereinproducing a plurality of optics elements comprises forming a pluralityof lenses separately from the wafer and attaching the lenses to thewafer at the device sites.
 37. An optical device assembly, comprising: asubstrate transmissive to a desired radiation, the substrate having aplurality of discrete device sites; and a plurality of optics elements,the optics elements being configured to direct radiation passing throughthe optics elements for use with microelectronic imagers, and the opticselements being located at corresponding device sites of the substrate toform individual optical devices at the device sites.
 38. The opticaldevice assembly of claim 37 wherein: the substrate comprises a waferconfigured to be processed in semiconductor fabrication tools, the waferbeing transmissive to light in the visible spectrum, and the waferhaving a first side and a second side; and the optics elements compriselenses on the first side of the wafer at the device sites, wherein eachlens has a curved surface to refract radiation.
 39. The optical deviceassembly of claim 38 wherein the lenses are molded elements each havinga curved surface, and the lenses being molded onto the wafer.
 40. Theoptical device assembly of claim 38 wherein the lenses are curvedsurfaces etched into the wafer.
 41. The optical device assembly of claim38 wherein the substrate further comprises a layer of lens material onthe wafer and the lenses are curved surfaces etched into the layer oflens material.
 42. The optical device assembly of claim 38 wherein thelenses are separate components each having a curved surface, and thelenses being attached individually to the wafer.
 43. The optical deviceassembly of claim 37 wherein the optics elements comprise lenses at thedevice sites, and each of the lenses has a first lens member on thefirst side of the wafer and a second lens member on the second side ofthe wafer.
 44. The optical device assembly of claim 37 furthercomprising a filter.
 45. The optical device assembly of claim 44 whereinthe filter comprises a filter layer deposited over the wafer thatfilters the radiation.
 46. The optical device assembly of claim 37wherein the optics elements comprise lenses on the first side of thewafer and pin-hole openings at the device sites, wherein each lens has acurved surface to refract radiation.
 47. An optical device assemblycomprising a plurality of individual optical devices on a singlesubstrate, individual optical devices each including an optics elementconfigured to alter the direction of radiation passing through theoptical device, and the optics element of one optical device beingseparated from the optics element of an adjacent optical device by acutting lane for subsequently cutting the substrate to separate theindividual optical devices from each other.
 48. The optical deviceassembly of claim 47 wherein: the substrate comprises a wafer configuredto be processed in semiconductor fabrication tools, the wafer beingtransmissive to light in the visible spectrum, and the wafer having afirst side and a second side; and the optics elements comprise lenses onthe first side of the wafer at the device sites, wherein each lens has acurved surface to refract radiation.
 49. The optical device assembly ofclaim 48 wherein the lenses are molded elements each having a curvedsurface, and the lenses being molded onto the wafer.
 50. The opticaldevice assembly of claim 48 wherein the lenses are curved surfacesetched into the wafer.
 51. The optical device assembly of claim 48wherein the lenses are separate components each having a curved surface,and the lenses being attached individually to the wafer.
 52. The opticaldevice assembly of claim 47 wherein the optics elements comprise lensesat the device sites, and each of the lenses has a first lens member onthe first side of the wafer and a second lens member on the second sideof the wafer.
 53. The optical device assembly of claim 48 furthercomprising a filter.
 54. The optical device assembly of claim 47 whereinthe optics elements comprise lenses on the first side of the wafer andpin-hole openings at the device sites, wherein each lens has a curvedsurface to refract radiation.
 55. An optical device assembly,comprising: a substrate transmissive to a desired radiation, thesubstrate having a first device site and a second device site; a firstoptics element at the first device site to form a first optical deviceand a second optics element at the second device site to form a secondoptical device, wherein the first and second optics elements areseparated by a cutting lane to subsequently separate the first opticaldevice from the second optical device.
 56. The optical device assemblyof claim 55 wherein: the substrate comprises a wafer configured to beprocessed in semiconductor fabrication tools, the wafer beingtransmissive to light in the visible spectrum, and the wafer having afirst side and a second side; and the optics elements comprise lenses onthe first side of the wafer at the device sites, wherein each lens has acurved surface to refract radiation.
 57. The optical device assembly ofclaim 56 wherein the lenses are molded elements each having a curvedsurface, and the lenses being molded onto the wafer.
 58. The opticaldevice assembly of claim 56 wherein the lenses are curved surfacesetched into the wafer.
 59. The optical device assembly of claim 56wherein the substrate further comprises a layer of lens material on thewafer and the lenses are curved surfaces etched into the layer of lensmaterial.
 60. The optical device assembly of claim 56 wherein the lensesare separate components each having a curved surface, and the lensesbeing attached individually to the wafer.